diff options
| -rw-r--r-- | fs/btrfs/extent_io.c | 48 |
1 files changed, 17 insertions, 31 deletions
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 0c4a305aa5cb..36d80cb8cfa3 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -4396,28 +4396,6 @@ static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned return distance < len; } -static void copy_pages(struct page *dst_page, struct page *src_page, - unsigned long dst_off, unsigned long src_off, - unsigned long len) -{ - char *dst_kaddr = page_address(dst_page); - char *src_kaddr; - int must_memmove = 0; - - if (dst_page != src_page) { - src_kaddr = page_address(src_page); - } else { - src_kaddr = dst_kaddr; - if (areas_overlap(src_off, dst_off, len)) - must_memmove = 1; - } - - if (must_memmove) - memmove(dst_kaddr + dst_off, src_kaddr + src_off, len); - else - memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); -} - void memcpy_extent_buffer(const struct extent_buffer *dst, unsigned long dst_offset, unsigned long src_offset, unsigned long len) @@ -4448,23 +4426,26 @@ void memmove_extent_buffer(const struct extent_buffer *dst, unsigned long dst_offset, unsigned long src_offset, unsigned long len) { - size_t cur; - size_t dst_off_in_page; - size_t src_off_in_page; unsigned long dst_end = dst_offset + len - 1; unsigned long src_end = src_offset + len - 1; - unsigned long dst_i; - unsigned long src_i; if (check_eb_range(dst, dst_offset, len) || check_eb_range(dst, src_offset, len)) return; + if (dst_offset < src_offset) { memcpy_extent_buffer(dst, dst_offset, src_offset, len); return; } + while (len > 0) { - dst_i = get_eb_page_index(dst_end); + unsigned long src_i; + size_t cur; + size_t dst_off_in_page; + size_t src_off_in_page; + void *src_addr; + bool use_memmove; + src_i = get_eb_page_index(src_end); dst_off_in_page = get_eb_offset_in_page(dst, dst_end); @@ -4472,9 +4453,14 @@ void memmove_extent_buffer(const struct extent_buffer *dst, cur = min_t(unsigned long, len, src_off_in_page + 1); cur = min(cur, dst_off_in_page + 1); - copy_pages(dst->pages[dst_i], dst->pages[src_i], - dst_off_in_page - cur + 1, - src_off_in_page - cur + 1, cur); + + src_addr = page_address(dst->pages[src_i]) + src_off_in_page - + cur + 1; + use_memmove = areas_overlap(src_end - cur + 1, dst_end - cur + 1, + cur); + + __write_extent_buffer(dst, src_addr, dst_end - cur + 1, cur, + use_memmove); dst_end -= cur; src_end -= cur; |